Digest::HMAC(3pm) User Contributed Perl Documentation Digest::HMAC(3pm)NAMEDigest::HMAC - Keyed-Hashing for Message Authentication
SYNOPSIS
# Functional style
use Digest::HMAC qw(hmac hmac_hex);
$digest = hmac($data, $key, \&myhash);
print hmac_hex($data, $key, \&myhash);
# OO style
use Digest::HMAC;
$hmac = Digest::HMAC->new($key, "Digest::MyHash");
$hmac->add($data);
$hmac->addfile(*FILE);
$digest = $hmac->digest;
$digest = $hmac->hexdigest;
$digest = $hmac->b64digest;
DESCRIPTION
HMAC is used for message integrity checks between two parties that
share a secret key, and works in combination with some other Digest
algorithm, usually MD5 or SHA-1. The HMAC mechanism is described in
RFC 2104.
HMAC follow the common "Digest::" interface, but the constructor takes
the secret key and the name of some other simple "Digest::" as
argument.
The hmac() and hmac_hex() functions and the Digest::HMAC->new()
constructor takes an optional $blocksize argument as well. The HMAC
algorithm assumes the digester to hash by iterating a basic compression
function on blocks of data and the $blocksize should match the byte-
length of such blocks.
The default $blocksize is 64 which is suitable for the MD5 and SHA-1
digest functions. For stronger algorithms the blocksize probably needs
to be increased.
SEE ALSO
Digest::HMAC_MD5, Digest::HMAC_SHA1
RFC 2104
AUTHORS
Graham Barr <gbarr@ti.com>, Gisle Aas <gisle@aas.no>
perl v5.12.4 2011-07-25 Digest::HMAC(3pm)